在 2022/7/26 12:25, Jason Wang 写道:
在 2022/7/18 19:17, Kangjie Xu 写道:
Support queue enable in vhost-user scenario. It will be called when
a vq reset operation is performed and the vq will be restared.
It should be noted that we can restart the vq when the vhost has
already started. When launching a new vhost-user device, the vhost
is not started and all vqs are not initalized until
VIRTIO_PCI_COMMON_STATUS is written. Thus, we should use vhost_started
to differentiate the two cases: vq reset and device start.
Signed-off-by: Kangjie Xu <kangjie...@linux.alibaba.com>
Signed-off-by: Xuan Zhuo <xuanz...@linux.alibaba.com>
---
hw/net/virtio-net.c | 20 ++++++++++++++++++++
1 file changed, 20 insertions(+)
diff --git a/hw/net/virtio-net.c b/hw/net/virtio-net.c
index 8396e21a67..2c26e2ef73 100644
--- a/hw/net/virtio-net.c
+++ b/hw/net/virtio-net.c
@@ -544,6 +544,25 @@ static void virtio_net_queue_reset(VirtIODevice
*vdev, uint32_t queue_index)
assert(!virtio_net_get_subqueue(nc)->async_tx.elem);
}
+static void virtio_net_queue_enable(VirtIODevice *vdev, uint32_t
queue_index)
+{
+ VirtIONet *n = VIRTIO_NET(vdev);
+ NetClientState *nc = qemu_get_subqueue(n->nic, vq2q(queue_index));
+ int r;
+
+ if (!nc->peer || !vdev->vhost_started) {
+ return;
+ }
+
+ if (nc->peer->info->type == NET_CLIENT_DRIVER_VHOST_USER) {
+ r = vhost_virtqueue_restart(vdev, nc, queue_index);
+ if (r < 0) {
+ error_report("unable to restart vhost net virtqueue: %d, "
+ "when resetting the queue", queue_index);
+ }
+ }
+}
So we don't check queue_enable in vhost_dev_start(), does this mean
the queue_enable is actually meaningless (since the virtqueue is
already started there)?
And another issue is
peet_attach/peer_detach() "abuse" vhost_set_vring_enable(). This
probably means we need to invent new type of request instead of
re-using VHOST_USER_SET_VRING_ENABLE.
Thanks
1. Yes, we don't need queue_enable in vhost_dev_start(), queue_enable is
only useful when restarting the queue. I name it as queue_enable()
simply because it is called when VIRTIO_PCI_COMMON_Q_ENABLE is written.
Would it look better if we rename it as "queue_reenable"?
2. I think inventing a new type of vhost-protocol message can be a good
choice. However, I don't know much about the vhost protocol. If we want
to add a new message in vhost protocol, except the documentation and the
code in qemu, Do we need to submit patches to other projects, e.g. some
projects like virtio-spec?
Thanks
+
static void virtio_net_reset(VirtIODevice *vdev)
{
VirtIONet *n = VIRTIO_NET(vdev);
@@ -3781,6 +3800,7 @@ static void virtio_net_class_init(ObjectClass
*klass, void *data)
vdc->bad_features = virtio_net_bad_features;
vdc->reset = virtio_net_reset;
vdc->queue_reset = virtio_net_queue_reset;
+ vdc->queue_enable = virtio_net_queue_enable;
vdc->set_status = virtio_net_set_status;
vdc->guest_notifier_mask = virtio_net_guest_notifier_mask;
vdc->guest_notifier_pending = virtio_net_guest_notifier_pending;
